Mark IV tank

Mark IV
Mark IV male with unditching beam deployed
Type	Heavy tank
Place of origin	United Kingdom
Service history
Used by	British Army Imperial German Army Reichswehr Imperial Japanese Army
Wars	First World War German Revolution of 1918–19
Production history
Designer	Walter Gordon Wilson William Tritton
Manufacturer	see text
Unit cost	about £5,000 [1]
Produced	May 1917 – end 1918
No. built	1,220
Specifications
Mass	28 tons (28.4 tonnes) Female: 27 tons (27.4 tonnes)
Length	26 ft 5 in (8.05 m)
Width	Male: 13 ft 6 in (4.12 m)
Crew	8
Armour	0.5 inches (12 mm)
Main armament	Male: Two 6-pounder (57-mm) 6 cwt QF guns with 332 rounds Female: five .303 Lewis guns
Secondary armament	Male: Three .303 in Lewis guns
Engine	Daimler-Foster, 6-cylinder in-line sleeve valve 16 litre petrol engine 105 bhp at 1,000 rpm
Transmission	Primary: 2 Forward, 1 Reverse Secondary – 2 speed
Fuel capacity	70 Imperial gallons
Operational range	35 mi (56 km)
Maximum speed	4 mph (6.4 km/h)

The Mark IV (pronounced Mark four) was a British tank of the First World War. Introduced in 1917, it benefited from significant developments of the Mark I tank (the intervening designs being small batches used for training). The main improvements were in armour, the re-siting of the fuel tank and ease of transport. A total of 1,220 Mk IV were built: 420 "Males", 595 "Females" and 205 Tank Tenders (unarmed vehicles used to carry supplies), which made it the most numerous British tank of the war. The Mark IV was first used in mid 1917 at the Battle of Messines Ridge. It remained in British service until the end of the war, and a small number served briefly with other combatants afterwards.